Create single activity for rewrite rule

[rajkumar-rangaraj]

Addressing Issue #73

Changes

(Please provide a brief description of the changes here.)

Modified EndRequest in TelemetryCorrelationHttpModule to skip activity creation for rewrite generated parent request.

Background Information

Initial version of the TelemetryCorrelationHttpModule had this activity creation within Application_Error and later moved to EndRequest.

https://github.com/aspnet/Microsoft.AspNet.TelemetryCorrelation/pull/1/files
https://github.com/aspnet/Microsoft.AspNet.TelemetryCorrelation/blob/cc1592d241fee1df40442790fddf7779c787e838/src/Microsoft.AspNet.Diagnostics/DiagnosticsHttpModule.cs

#2
https://github.com/aspnet/Microsoft.AspNet.TelemetryCorrelation/blob/c0c6b8ce9e3f371c6012a2646e4a5f253fcaea41/src/Microsoft.AspNet.Diagnostics/DiagnosticsHttpModule.cs

Notes from PR

[ghost]

All CLA requirements met.

[SergeyKanzhelev]

ideally somebody from asp.net team needs to comment on any other situation this may have happened. I can think of one off the top of my head - if there is another module registered before this module and it returned 401 or some actual content from the BeginRequest call. Than Begin will not be called for this module at all. And we will end up loosing the fact of this call.

[SergeyKanzhelev]

Specifically for UrlRewrite, @TimothyMothra was working on logic that ensured that those will be parented to each other. This logic is somewhere in Application Insights http module. I wonder if this is a different case or the same

[rajkumar-rangaraj]

@SergeyKanzhelev, @TimothyMothra has worked on a change in application insights where parent and child request has same HttpContext. In this scenario, HttpContext generated at parent and child are different. I internally worked with IIS engineering team to check for the scenarios and came up with this change.

I will investigate the 401 error.

[rajkumar-rangaraj]

• Created new HttpModule and registered before TelemetryCorrelationHttpModule in pipeline

	  <modules>
		  <add name="One" type="WebApplication1.MyHttpModule1"/>
		  <add name="TelemetryCorrelationHttpModule" type="Microsoft.AspNet.TelemetryCorrelation.TelemetryCorrelationHttpModule, Microsoft.AspNet.TelemetryCorrelation" preCondition="managedHandler"/>
	  </modules>

• Added below code to BeginRequest of custom module to respond with HTTP 401.

        private void Application_BeginRequest(object sender, EventArgs e)
        {
            var context = ((HttpApplication)sender).Context;
            context.Response.StatusCode = (int)HttpStatusCode.Unauthorized;
        }

Requested got executed in below order and Activity got created

1. MyHttpModule1.BeginRequest
2. TelemetryCorrelationHttpModule.BeginRequest
3. MyHttpModule1.EndRequest
4. TelemetryCorrelationHttpModule.EndRequest

Will check if we could get someone from ASP.NET team to review this one.

[SergeyKanzhelev]

try to end the response after setting the status. Otherwise the module doesn't actually behave as authentication module as it continues an execution.

[SergeyKanzhelev]

Commented

[reyang]

LGTM and it meets with the recommendation we've got from ASP.NET team.

[reyang]

LGTM.